This tunnel needs the kind of facility that some tunnels on 101 in Oregon have. Cyclist pushes a button, and when the flashing yellow lights start blinking, they enter the tunnel and take the lane. There are big signs outside the tunnel saying that when the lights are blinking, there are cyclists in the tunnel, slow down, yield to them, exercise caution, etc. There's either some sensor that shuts off the lights when the cyclist leaves the tunnel, or it's on a timer. Motorists seem to respect it.